A chitosan-based edible film with clove essential oil and nisin for improving the quality and shelf life of pork patties in cold storage

A grafting approach for nisin-chitosan bio-based antibacterial films: preparation and characterization

Nisin is a bacteriocin produced by Gram-positive lactic acid bacterium,Lactococcus lactisand currently recognized in the Generally Recognızed as Safe (GRAS) category due to its non-toxicity. Herein, nisin has been grafted to chitosan structure to obtain natural bio-active films with enhanced antibacterial activity. Grafting was performed using ethyl ester lysine diisocyanate and dimer fatty acid-based diisocyanate (DDI); two different close to fully bio-based diisocyanates and Disuccinimidyl suberate; a homo-bifunctional molecule acting as a crosslinker between amino groups. The grafting process allowed the chemical immobilization of nisin to chitosan structure. Physicochemical characterization studies showed the successful grafting of nisin. The antibacterial activity againstStaphylococcus aureuswas evident for all nisin modified chitosan films and best pronounced when DDI was used as a crosslinker with a maximum zone of inhibition of ∼13 mm. All nisin grafted chitosan films were cytocompatible and the cell viability of L929 fibroblasts were >80% pointing out the non-toxic structure. Considering the results of the presented study, bio-based diisocyanates and homo-bifunctional crosslinkers are effective molecules in synthesis of nisin grafted chitosan structures and the new chitosan based antibacterial biopolymers obtained after nisin modification come forward as promising non-toxic and bioactive candidates to be applied in medical devices, implants, and various food coating products.

Clove Essential Oil: Chemical Profile, Biological Activities, Encapsulation Strategies, and Food Applications

Plants have proven to be important sources for discovering new compounds that are useful in the treatment of various diseases due to their phytoconstituents. Clove (Syzygium aromaticum L.), an aromatic plant widely cultivated around the world, has been traditionally used for food preservation and medicinal purposes. In particular, clove essential oil (CEO) has attracted attention for containing various bioactive compounds, such as phenolics (eugenol and eugenol acetate), terpenes (β-caryophyllene and α-humulene), and hydrocarbons. These constituents have found applications in cosmetics, food, and medicine industries due to their bioactivity. Pharmacologically, CEO has been tested against a variety of parasites and pathogenic microorganisms, demonstrating antibacterial and antifungal properties. Additionally, many studies have also demonstrated the analgesic, antioxidant, anticancer, antiseptic, and anti-inflammatory effects of this essential oil. However, CEO could degrade for different reasons, impacting its quality and bioactivity. To address this challenge, encapsulation is viewed as a promising strategy that could prolong the shelf life of CEO, improving its physicochemical stability and application in various areas. This review examines the phytochemical composition and biological activities of CEO and its constituents, as well as extraction methods to obtain it. Moreover, encapsulation strategies for CEO and numerous applications in different food fields are also highlighted.

Polysaccharide film containing cinnamaldehyde-chitosan nanoparticles, a new eco-packaging material effective in meat preservation

The development of novel eco-friendly materials like chitosan for food storage and preservation has become crucial in eliminating plastic packaging and minimizing waste. In this work, cinnamaldehyde has been encapsulated in chitosan nanoparticles and subsequently incorporated into a 2 % chitosan film. The obtained nanoparticles achieved an average radius size of 89.80 nm, PDI of 0.40, and spherical morphology determined by SEM. Cinnamaldehyde was encapsulated in chitosan nanoparticles achieving values of encapsulation close to 7 %, showing a biphasic release profile with sustained release during 5 days. Films with an average thickness of 0.124 mm and elongation at break of 63.66 % to 76.50 % were obtained. Finally, the antimicrobial properties of the films was tested showing reduction values in total aerobic value of 4.85 log cfu/g, total coliform of 1.26 log cfu/g and grow potential value of < 0.5 log10 for Listeria monocitogenes over 20 days.

Inhibitory effects of citral on the production of virulence factors in Staphylococcus aureus and its potential application in meat preservation

Foodborne diseases caused by Staphylococcus aureus contamination on meat and meat products has gained increasing attention in recent years, while the pathogenicity of S. aureus is mainly attributed to its virulence factors production, which is primarily regulated by quorum sensing (QS) system. Herein, we aimed to uncover the inhibitory effects and mechanisms of citral (CIT) on virulence factors production by S. aureus, and further explore its potential application in pork preservation. Susceptibility test confirmed the antibacterial properties of CIT against S. aureus, the minimal inhibitory concentration (MIC) was 0.25 mg/mL. Treatment with sub-MICs of CIT reduced the hemolytic activity by inhibiting the production of α-hemolysin, and staphylococcal enterotoxins (SEs) production was significantly inhibited by CIT in both culture medium and pork without affecting bacterial growth. Transcriptomic analysis indicated that the differentially expression genes encoding α-hemolysin, SEs, and other virulence factors were down-regulated after treatment with 1/2MIC CIT. Moreover, the genes related to QS including agrA and agrC were also down-regulated, while the global transcriptional regulator sarA was up-regulated. Data here demonstrated that CIT could inhibited S. aureus virulence factors production through disturbing QS systems. In a challenge test, the addition of CIT caused a remarkable inhibition of S. aureus population and delay in lipid oxidation and color change on pork after 15 days incubation at 4 °C. These findings demonstrated that CIT could not only efficiently restrain the production of S. aureus virulence factors by disturbing QS, but also exhibit the potential application on the preservation of meat products.

Application of chitosan films incorporated with Zanthoxylum limonella essential oil for extending shelf life of pork

This study aimed to produce chitosan films incorporated with Zanthoxylum limonella essential oil for extending shelf life. The volatile compounds of Z. limonella essential oil were identified by gas chromatography-mass spectrometry consisting of limonene, α-phellandrene, ρ-cymene, and sabinene as major compounds. In this study, the addition of Z. limonella essential oil at concentrations of 0 %, 2 %, and 4 % in chitosan film was assessed for its antibacterial activity against Escherichia coli and Staphylococcus aureus. Chitosan film incorporated with 4 % essential oil demonstrated the most significant antibacterial effect against E. coli and S. aureus in comparison to the chitosan film without essential oil due to the synergistic effects on antibacterial activity. The physical and mechanical properties of the chitosan films incorporated with Z. limonella oil developed were also assessed. The addition of essential oil to chitosan films led to improvements in mechanical strength and flexibility, while minimal changes were observed in terms of water solubility, water vapor permeability, and thermal stability. The findings emphasize that this innovative film not only extends the shelf life of pork without chemical preservatives but is also a fully bio-based material. Consequently, it shows great potential to be used as active packaging within the food industry.

Effect of dietary fat on proximal composition, sensorial analysis and shelf life of a traditional Spanish cooked pork product "Lomo de Sajonia" from Iberian pork

This study aims to evaluate the effect of different dietary fat sources on the quality of a Spanish-cooked meat product Lomo de Sajonia (LSA) and its shelf-life. Forty loins were selected from Iberian pigs fed four dietary treatments containing pork fat (G-1), Greedy-Grass Olive® (GGO) (enriched oleic-acid oil) (G-2), G-2 and high oleic sunflower (G-3), and G-3 plus a mixture of commercial organic acids (Bioll®) (G-4). Loins were manufactured to obtain LSA, and the quality and sensorial attributes were assessed. The shelf life was established according to microbial count and sensorial analysis, which was packed in a modified atmosphere and stored under retail conditions. All meat quality parameters of LSA remained stable in all groups, except fat content and overall liking, which showed the highest values for G-2 LSA. Regarding the shelf life, sensorial attributes remained acceptable in all groups during storage time, while a delay in microbial growth was recorded for the LSA of G-3. According to the results, including GGO in Iberian pig diets could enhance LSA traits, possibly linked to increased assimilation compared with conventional fat sources. However, adding organic acids to the diet did not have the expected effect on improving the shelf life of the LSA.

Application of chitosan and other biopolymers based edible coatings containing essential oils as green and innovative strategy for preservation of perishable food products: A review

Deterioration of perishable foods due to fungal contamination and lipid peroxidation are the most threatened concern to food industry. Different chemical preservatives have been used to overcome these constrains; however their repetitive use has been cautioned owing to their negative impact after consumption. Therefore, attention has been paid to essential oils (EOs) because of their natural origin and proven antifungal and antioxidant activities. Many EO-based formulations have been in use but their industrial-scale application is still limited, possibly due to its poor solubility, vulnerability towards oxidation, and aroma effect on treated foods. In this sense, active food packaging using biopolymers could be considered as promising approach. The biopolymers can enhance the stability and effectiveness of EOs through controlled release, thus minimizes the deterioration of foods caused by fungal pathogens and oxidation without compromising their sensory properties. This review gives a concise appraisal on latest advances in active food packaging, particularly developed from natural polymers (chitosan, cellulose, cyclodextrins etc.), characteristics of biopolymers, and current status of EOs. Then, different packaging and their effectiveness against fungal pathogens, lipid-oxidation, and sensory properties with recent previous works has been discussed. Finally, effort was made to highlights their safety and commercialization aspects towards market solutions.

Effect of Edible Coating Made from Arrowroot Flour and Kaffir Lime Leaf Essential Oil on the Quality Changes of Pork Sausage under Prolonged Refrigerated Storage

Edible coatings are pivotal in enhancing the quality of processed meat products, acting as barriers to environmental and microbial influences by adhering directly to the food surface. Arrowroot flour, a widely produced edible tuber in Thailand, is uncharted in terms of its capability and effectiveness as an edible coating on food materials. This study aims to elucidate the composition and spectral properties of arrowroot tuber flour (ATF) to discern its viability as an edible coating for pork sausages. ATF exhibited a composition predominantly featuring carbohydrates (74.78%), moisture (9.59%), and protein (8.89%), underlining its appropriateness as an edible coating. Rapid visco amylograph revealed ATF's significant pasting capability. This study incorporated kaffir lime leaves essential oil (KEO) into the ATF coating in diverse concentrations (0-3%). Fourier-transform Infrared spectroscopy illuminated characteristic peaks and bands, showing observable shifts with the integration of KEO, yet the majority of peak placements remained essentially unchanged. The microstructure of the coatings maintained its homogeneity at heightened KEO concentrations, reflecting compatibility with ATF. The efficacy of the ATF-KEO coatings was evaluated on pork sausages, using uncoated samples as controls. While color modifications were evident, coated sausages maintained consistent moisture content, water activity, and pH levels throughout the storage duration. The coated samples also manifested enhanced textural attributes and a decline in lipid oxidation, as evidenced by reduced TBARS levels compared to controls. A subsequent microbial examination corroborated the inhibitory capacity of the ATF-KEO coatings on the microbial proliferation in pork sausages, encapsulating Total Viable Count (TVC), psychrotrophic bacteria, and lactic acid bacteria. In conclusion, the findings substantiate the promising application of ATF, especially in synergy with KEO, as a proficient edible coating for meat products. This combination aids in preserving color and texture, impeding microbial advancement, and moderating lipid oxidation, thereby contributing to the overall quality and safety of the products.

Development and application of fruit and vegetable based green films with natural bio-actives in meat and dairy products: a review

In recent years, foodborne outbreaks and food plastic waste accumulation in the environment have impelled a hunt for new, sustainable, novel and innovatory food packaging interventions to face microbial contamination, food quality and safety. Pollution caused from wastes generated by agricultural activities is one of chief rising concerns of the environmentalists across the globe. A solution to this problem is effective and economic valorization of residues from agriculture sector. It would ensure that the by-products/residues from one activity act as ingredients/raw materials for another industry. An example is fruit and vegetable waste based green films for food packaging. Edible packaging is a well-researched area of science where numerous biomaterials have been already explored. Along with dynamic barrier properties, these biofilms often exhibit antioxidant and antimicrobial properties as function of the bioactive additives (e.g. essential oils) often incorporated in them. Additionally, these films are made competent by use of recent technologies (e.g. encapsulation, nano-emulsions, radio-sensors) to ensure high end performance and meet the principles of sustainability. Livestock products such as meat, poultry and dairy products are highly perishable and depend largely upon the mercy of packaging materials to enhance their shelf life. In this review, all the above-mentioned aspects are thoroughly covered with a view to project fruit and vegetable based green films (FVBGFs) as a potential and viable packaging material for livestock products, along with a discussion on role of bio-additives, technological interventions, properties and potential applications of FVBGFs in livestock products. © 2023 Society of Chemical Industry.

Potential Impact of Combined Inhibition by Bacteriocins and Chemical Substances of Foodborne Pathogenic and Spoilage Bacteria: A Review

In recent years, food safety caused by foodborne pathogens and spoilage bacteria has become a major public health problem worldwide. Bacteriocins are a kind of antibacterial peptide synthesized by microbial ribosomes, and are widely used as food preservatives. However, when used individually bacteriocins may have limitations such as high cost of isolation and purification, narrow inhibitory spectrum, easy degradation by enzymes, and vulnerability to complex food environments. Numerous studies have demonstrated that co-treatment with bacteriocins and a variety of chemical substances can have synergistic antibacterial effects on spoilage microorganisms and foodborne pathogens, effectively prolonging the shelf life of food and ensuring food safety. Therefore, this paper systematically summarizes the synergistic bacteriostatic strategies of bacteriocins in combination with chemical substances such as essential oils, plant extracts, and organic acids. The impacts of bacteriocins when used individually and in combination with other chemical substances on different food substrates are clarified, and bacteriocin-chemical substance compositions that enhance antibacterial effectiveness and reduce the potential negative effects of chemical preservatives are highlighted and discussed. Combined treatments involving bacteriocins and different kinds of chemical substances are expected to be a promising new antibacterial method and to become widely used in both the food industry and biological medicine.

Investigating the microbial properties of sodium alginate/chitosan edible film containing red beetroot anthocyanin extract for smart packaging in chicken fillet as a pH indicator

The current trend in the production of smart films involves the use of pH-responsive color indicators derived from natural sources. In line with this trend, the aim of this research is to produce edible films from sodium alginate (A) and chitosan (Ch) incorporating red beet anthocyanin (Ac) extract, and to assess the properties of these films and their use as coatings for chicken fillets. The study employed a factorial design to evaluate the effects of treatments C (control), A25%-ch75% (films consisting of 25% sodium alginate and 75% chitosan), and A25%-ch75%-Ac (films consisting of 25% sodium alginate, 75% chitosan, and red beet anthocyanin). The findings indicate that the inclusion of red beet anthocyanin extract did not result in any discernible differences in the FTIR spectra of the film samples. Analysis of the XRD results revealed that the addition of the extract led to a reduction in the crystal structure of the film. Moreover, SEM results demonstrated that the extract caused alterations in the polymer chains and an increase in the porosity of the film matrix. With regard to the chicken fillet samples coated with the film, over time, there was an increase in microbial analysis (total microorganism count and Staphylococcus aureus coagulase-positive) and chemical properties (pH, peroxide, thiobarbituric acid, and nitrogen compounds) for all samples. However, this trend was significantly lower in the samples coated with the Ac extract (P < 0.05). Texture analysis results revealed that the hardness parameter of all samples decreased over the storage period, while the samples containing the Ac extract demonstrated a significant increase in this parameter (P < 0.05). Additionally, the color changes of the pH sensor corresponded to the anthocyanin structure. Based on the results, the smart film composed of sodium alginate/chitosan incorporating red beet anthocyanin extract has the potential to enhance the quality, prolong the shelf life, and decrease the microbial load of chicken fillet when used as a coating. Furthermore, red beet anthocyanin can serve as a suitable indicator for spoilage changes in packaged food products.

Antimicrobial and Antioxidant Edible Films and Coatings in the Shelf-Life Improvement of Chicken Meat

Meat deterioration during processing, distribution, and display can compromise the quality and safety of products, causing several undesirable changes and decreasing products' shelf-life, which has a negative impact on the industry and consumers. In recent years, studies have been carried out using decontamination techniques and new packaging methodologies to overcome deterioration problems, increase sustainability, and reduce waste. Edible films and coatings obtained from biopolymers such as polysaccharides, proteins, and lipids, combined with active compounds, can be an alternative approach. This article focused on recent studies that used alternative biodegradable polymeric matrices in conjunction with natural compounds with antioxidant/antimicrobial activity on chicken meat. Its impact on physicochemical, microbiological, and sensory characteristics was evident, as well as the effect on its shelf-life. In general, different combinations of active edible films or coatings had a positive effect on the chicken meat. Different studies reported that the main results were a decrease in microbial growth and pathogen survival, a slowdown in lipid oxidation evolution, and an improvement in sensory quality and shelf-life (an increase from 4 to 12 days).

Fortification of polysaccharide-based packaging films and coatings with essential oils: A review of their preparation and use in meat preservation

As the demand for botanical food additives and eco-friendly food packaging materials grows, the use of essential oils, edible biodegradable films and coatings are becoming more popular in packaging. In this review, we discussed the recent research trends in the use of natural essential oils, as well as polysaccharide-based coatings and films: from the composition of the substrates to preparing formulations for the production of film-forming technologies. Our review emphasized the functional properties of polysaccharide-based edible films that contain plant essential oils. The interactions between essential oils and other ingredients in edible films and coatings including polysaccharides, lipids, and proteins were discussed along with effects on film physical properties, essential oil release, their active role in meat preservation. We presented the opportunities and challenges related to edible films and coatings including essential oils to increase their industrial value and inform the development of edible biodegradable packaging, bio-based functional materials, and innovative food preservation technologies.

Bioactive zein/chitosan systems loaded with essential oils for food-packaging applications

BACKGROUND

There has recently been increased interest in biodegradable and sustainable packaging within the food industry. Biopolymer materials based on renewable biomass can be used as alternatives to conventional plastic packaging. A corn protein, zein, possesses excellent film-forming properties because of its hydrophobic nature. It can be used for making edible films and for producing nanofibrous layers. Combination with polysaccharides like chitosan offers promising prospects for the production of delivery systems for the controlled release of active substances. The current trend is to minimize the content of chemical additives; thus essential oils are suitable alternatives to synthetic antimicrobials.

RESULTS

This study aimed to develop various zein/chitosan-based film-forming solutions, films, and coatings with antimicrobial substances to prepare active food packaging. Thymol and three essential oils (thyme, cinnamon, oregano) were applied as bioactive ingredients against bacteria, yeasts, and fungi. The incorporation of these natural active compounds led to a decrease in particle size in most film-forming solutions and a reduction of zeta potential compared to controls. Release of the bioactive compound into an aqueous environment was proved by antimicrobial test. A zein/chitosan-based coating with thymol was applied on fresh strawberries. Microbiological analysis over 10 days confirmed the efficient control of bacterial and fungal growth.

CONCLUSION

Zein/chitosan (7:1) systems are suitable as bioactive compound carriers to make barriers and to prevent moisture loss, ensuring microbial food quality and prolonging the shelf life of fruits. These systems can serve as sustainable active food packaging. © 2022 Society of Chemical Industry.

The Emergence of Edible and Food-Application Coatings for Food Packaging: A Review

Food packaging was not as important in the past as it is now, because the world has more people but fewer food resources. Food packaging will become more prevalent and go from being a nice-to-have to an essential feature of modern life. Food packaging has grown to be an important industry sector in today's world of more people and more food. Food packaging innovation faces significant challenges in extending perishable food products' shelf life and contributing to meeting daily nutrient requirements as people nowadays are searching for foods that offer additional health advantages. Modern food preservation techniques have two objectives: process viability and safe, environmentally friendly end products. Long-term storage techniques can include the use of edible coatings and films. This article gives a succinct overview of the supplies and procedures used to coat food products with conventional packaging films and coatings. The key findings summarizing the biodegradable packaging materials are emphasized for their ability to prolong the freshness and flavor of a wide range of food items; films and edible coatings are highlighted as viable alternatives to traditional packaging methods. We discuss the safety concerns and opportunities presented by applying edible films and coatings, allowing it to be used as quality indicators for time-sensitive foods.

A novel composite edible film fabricated by incorporating W/O/W emulsion into a chitosan film to improve the protection of fresh fish meat

A novel edible composite film constructed by incorporating W₁/O/W₂ emulsion (W₁: aqueous solution of nisin; W₂: water; oil phase: carvacrol) into chitosan film was characterized. Influences of preparing parameters on properties, especially stability, of primary and double emulsions were evaluated, and more persistent antibacterial activity was achieved. The film's tension strength was increased by incorporating double emulsion at low concentration, but its oxygen permeability increased after this incorporation. The composite film displayed significant inhibitory effects on both Gram-positive and Gram-negative bacteria. SEM showed a sign of aggregation of some emulsion droplets near the surface of the composite film. FTIR found no pronounced interaction between the added active agents and chitosan. TGA proved that the double emulsion helped to increase the thermal stability of the film at high temperature. Coating salmon fillets with the composite film significantly increased the shelf life of fish fillets, demonstrating optimal potency in preserving fish fillets.

Application of an Eco-Friendly Antifungal Active Package to Extend the Shelf Life of Fresh Red Raspberry (Rubus idaeus L. cv. 'Kweli')

The main objective of this study was to extend the shelf life of fresh red raspberry (Rubus idaeus. L. cv. 'Kweli') by using active film-pads inside commercial compostable packages. The pads were produced with chitosan (Ch) with the incorporation of green tea (GTE) and rosemary (RSME) ethanolic extracts as natural antifungal agents. Pads were placed on the bottom of commercial fruit trays underneath the fruits, and the trays were heat-sealed with a polyacid lactic (PLA) film. Preservation studies were carried out over 14 days of storage at refrigeration temperature (4 °C). Raspberry samples were periodically analyzed throughout storage, in terms of quality attributes (fungal decay, weight loss, firmness, surface color, pH, total soluble solids), total phenolic content and antioxidant activity. Gas composition inside the packages was also analyzed over time. From the packaging systems tested, the ones with active film-pads Ch + GTE and Ch + RSME were highly effective in reducing fungal growth and decay of raspberry during storage, showing only around 13% and 5% of spoiled fruits after 14 days, respectively, in contrast with the packages without pads (around 80% of spoiled fruits detected). In addition, fruits preserved using packages with Ch + RSME active film-pads showed lower mass loss (5.6%), decreased firmness (3.7%) and reduced antioxidant activity (around 9% and 15% for DPPH and FRAP methods, respectively). This sustainable packaging presents a potential strategy for the preservation of raspberries and other highly perishable small fruits.

Fabrication of electrospun nanofibers with moisture-triggered carvacrol release in fresh produce packaging

In this study, by incorporating polyethylene glycol (PEG) into the polylactic acid (PLA) nanofibers, a moisture-controlled system was developed in the release of carvacrol to the food package headspaces. With the use of electrospinning technology, an optimized solution (80:20 [PLA:PEG] polymer mixture incorporated with a carvacrol content of 20% [w/w polymer]) generated nanofibers with excellent encapsulation efficiency, loading capacity, and controlled release of carvacrol at different humidity levels. Carvacrol was prevented from release when the fibers were kept in dry states. When placed in food packaging with high humidity levels, the nanofibers manifested high and continuous release of carvacrol into the headspace. The shelf life of strawberries determined by visual inspection was extended for 2 extra days when packaged with the optimized nanofibers and had a significantly lower yeasts and mold counts (4.28 ± 0.34 log CFU/g) compared to strawberries packaged without nanofibers (5.22 ± 0.47 log CFU/g) 3 days after applying the nanofibers (p < 0.05). PRACTICAL APPLICATION: The nanofibers with PEG content as developed in this study represent a step forward in practical application of the electrospinning technology to enhance food quality in food preservation.

Application of Clove Oil and Sonication Process on the Influence of the Functional Properties of Mung Bean Flour-Based Edible Film

The present study was aimed to investigate the effects of sonication and clove oil incorporation on the improvement of physical, antioxidant, and antimicrobial properties and lipid oxidation inhibiting abilities of mung bean flour (MF)-based films. There were three groups of films tested (1) MF: mung bean flour alone, (2) MFC: MF incorporated with 2% clove oil (C), and (3) MFCU: MFC prepared with sonication (25 kHz, 100% amplitude, 10 min). Film thickness and bulk density showed slight differences, and moisture content, solubility, and water vapor permeability significantly differed between the formulations. Tensile strength, elongation at break, and Young’s modulus were highest for the MFCU films, followed by MFC and MF in rank order. Furthermore, the Fourier-transform infrared spectroscopy results also demonstrated that the clove oil and sonication treatment had improved the interconnections of the biopolymers, thus increasing the physical strength of the film. Phytochemicals in terms of total phenolics and total flavonoids were elevated in the MFCU films and contributed to stronger radical scavenging abilities (p < 0.05). MFC and MFCU films showed a strong antibacterial control of the Gram-positive Staphylococcus aureus (S. aureus) and also of the Gram-negative Campylobacter jejuni (C. jejuni). Overall, the lipid oxidation indicators Thiobarbituric acid reactive substances (TBARS, peroxide value, p-anisidine value, and totox value) showed significantly high inhibition, attributed to radical scavenging activities in the MFCU and MFC samples. The mung bean flour films incorporated with clove oil and prepared with sonication have good potential as packaging materials for food due to strong physical, antimicrobial, and antioxidant properties, as well as lipid oxidation inhibiting abilities.

Protective Impact of Chitosan Film Loaded Oregano and Thyme Essential Oil on the Microbial Profile and Quality Attributes of Beef Meat

Edible films and essential oil (EO) systems have the potency to enhance the microbial quality and shelf life of food. This investigation aimed to evaluate the efficacy of chitosan films including essential oils against spoilage bacteria and foodborne pathogens associated with meat. Antimicrobial activity (in vitro and in vivo) of chitosan films (CH) incorporated with oregano oil (OO) and thyme oil (TO) at 0.5 and 1% was done against spoilage bacteria and foodborne pathogens, compared to the control sample and CH alone. Preliminary experiments (in vitro) showed that the 1% OO and TO were more active against Staphylococcus aureus compared to Escherichia coli O157:H7 and Salmonella Typhimurium. In in vivo studies, CH containing OO and TO effectively inhibited the three foodborne pathogens and spoilage bacteria linked with packed beef meat which was kept at 4 °C/30 days compared to the control. The total phenolic content of the EOs was 201.52 mg GAE L-1 in thyme and 187.64 mg GAE L-1 in oregano. The antioxidant activity of thyme oil was higher than oregano oil. The results demonstrated that the shelf life of meat including CH with EOs was prolonged ~10 days compared to CH alone. Additionally, CH-OO and CH-TO have improved the sensory acceptability until 25 days, compared to the control. Results revealed that edible films made of chitosan and containing EOs improved the quality parameters and safety attributes of refrigerated or fresh meat.

Polysaccharide-Based Edible Films Incorporated with Essential Oil Nanoemulsions: Physico-Chemical, Mechanical Properties and Its Application in Food Preservation-A Review

Edible films with essential oils (EOs) are becoming increasingly popular as an alternative to synthetic packaging due to their environmentally friendly properties and ability as carriers of active compounds. However, the required amounts of EOs to impart effective antimicrobial properties generally exceed the organoleptic acceptance levels. However, by nanoemulsifying EOs, it is possible to increase their antimicrobial activity while reducing the amount required. This review provides an overview of the physico-chemical and mechanical properties of polysaccharide-based edible films incorporated with EOs nanoemulsions and of their application to the preservation of different food types. By incorporating EOs nanoemulsions into the packaging matrix, these edible films can help to extend the shelf-life of food products while also improving the quality and safety of the food product during storage. It can be concluded that these edible films have the potential to be used in the food industry as a green, sustainable, and biodegradable method for perishable foods preservation.

The Emergence and Impact of Ethylene Scavengers Techniques in Delaying the Ripening of Fruits and Vegetables

As the top grocery list priorities, the primary challenge when purchasing fruits and vegetables from supermarkets is obtaining fresh, minimally processed perishable goods. This source of diet is critical for obtaining vitamins, minerals, antioxidants, and fibres. However, the short shelf life caused by moisture content in rapid deterioration and decay caused by microbial growth, results in unappealing appearances. Fruits and vegetables undergo ripening and eventually the ageing process, in which the tissues of the plants degrade. Even after harvesting, numerous biological processes occur, generating a significant variation of ethylene production along with respiration rates between fruits and vegetables. Thus, the utilization of ethylene scavengers in food packaging or films has been revealed to be beneficial. The synergistic effects of these biomaterials have been demonstrated to reduce microorganisms and prolong the shelf life of greens due to antimicrobial activity, oxygen scavenging capacity, enzyme immobilization, texture enhancers, and nutraceuticals. The current review fills this void by discussing the most recent advances in research on ethylene scavengers and removal mechanisms of ethylene, including oxidation in fruit and vegetable packaging. The application and advantages of ethylene scavengers in packaging are then discussed with the addition of how the efficiency related to ethylene scavengers can be increased through atmospheric packaging tools. In this context, the article discusses characteristics, types of applications, and efficacy of ethylene control strategies for perishable commodities with the inclusion of future implications.

Sustainable edible packaging systems based on active compounds from food processing byproducts: A review

The global food processing industries represent a challenge and a risk to the environment due to the poor handling of residues, which are often discarded as waste without being used in further sidestreams. Although some part of this biomass is utilized, large quantities are, however, still under- or unutilized despite these byproducts being a rich resource of valuable compounds. These biowastes contain biopolymers and other compounds such as proteins, polysaccharides, lipids, pigments, micronutrients, and minerals with good nutritional values and active biological properties with applications in various fields including the development of sustainable food packaging. This review offers an update on the recent advancement of food byproducts recycling and upgrading toward the production of food packaging materials, which could be edible, (bio)degradable, and act as carriers of biobased active agents such as antimicrobials, antioxidants, flavoring additives, and health-promoting compounds. This should be a global initiative to promote the well-being of humans and achieve sustainability while respecting the ecological boundaries of our planet. Edible films and coatings formulations based on biopolymers and active compounds extracted from biowastes offer great opportunities to decrease the devastating overuse of plastic-based packaging. It has become evident that a transition from a fuel-based to a circular bio-based economy is potentially beneficial. Therefore, the exploitation of food discards within the context of a zero-waste biorefinery approach would improve waste management by minimizing its generation, reduce pollution, and provide value-added compounds. Most importantly, the development of edible packaging materials from food byproducts does not compete with food resources, and it also helps decrease our dependency on petroleum-based products. Practical Application Almost 99% of current plastics are petroleum-based, and their continuous use has been devastating to the planet as plastic-derived components have been detected in all trophic levels. Besides, the increasing amounts of food by-products are a socioeconomic and environmental challenge, and halving food loss and waste and turning it into valuable products has become necessary to achieve sustainability and economic circularity. The development of new packaging systems such as edible materials could be one of the solutions to limit the use of persistent plastics. Edible films and coatings by-products-based could also enhance food packaging performance due to their compounds' bioactivities.

Novel strategies of essential oils, chitosan, and nano- chitosan for inhibition of multi-drug resistant: E. coli O157:H7 and Listeria monocytogenes

Despite the wide range of available antibiotics, food borne bacteria demonstrate a huge spectrum of resistance. The current study aims to use natural components such as essential oils (EOs), chitosan, and nano-chitosan that have very influential antibacterial properties with novel technologies like chitosan solution/film loaded with EOs against multi-drug resistant bacteria. Two strains of Escherichia coli O157:H7 and three strains of Listeria monocytogenes were used to estimate antibiotics resistance. Ten EOs and their mixture, chitosan, nano-chitosan, chitosan plus EO solutions, and biodegradable chitosan film enriched with EOs were tested as antibacterial agents against pathogenic bacterial strains. Results showed that E. coli O157:H7 51,659 and L. monocytogenes 19,116 relatively exhibited considerable resistance to more than one single antibiotic. Turmeric, cumin, pepper black, and marjoram did not show any inhibition zone against L. monocytogenes; Whereas, clove, thyme, cinnamon, and garlic EOs exhibited high antibacterial activity against L. monocytogenes with minimum inhibitory concentration (MIC) of 250–400 μl 100⁻¹ ml and against E. coli O157:H7 with an MIC of 350–500 μl 100⁻¹ ml, respectively. Among combinations, clove, and thyme EOs showed the highest antibacterial activity against E. coli O157:H7 with MIC of 170 μl 100⁻¹ ml, and the combination of cinnamon and clove EOs showed the strongest antibacterial activity against L. monocytogenes with an MIC of 120 μl 100⁻¹ ml. Both chitosan and nano-chitosan showed a promising potential as an antibacterial agent against pathogenic bacteria as their MICs were relatively lower against L. monocytogenes than for E. coli O157:H7. Chitosan combined with each of cinnamon, clove, and thyme oil have a more effective antibacterial activity against L. monocytogenes and E. coli O157:H7 than the mixture of oils alone. Furthermore, the use of either chitosan solution or biodegradable chitosan film loaded with a combination of clove and thyme EOs had the strongest antibacterial activity against L. monocytogenes and E. coli O157:H7. However, chitosan film without EOs did not exhibit an inhibition zone against the tested bacterial strains.

Natural Antimicrobials as Additives for Edible Food Packaging Applications: A Review

Edible packaging is a swiftly emerging art of science in which edible biopolymers like lipids, polysaccharides, proteins, resins, etc., and other consumable constituents extracted from various non-conventional sources are used alone or imbibed together. Edible packaging with antimicrobial components had led to the development of the hypothesis of active packaging which safeguards the quality of foods as well as health of consumers. Natural antimicrobial agents (NAMAs) like essential oils from spices, bioactive compounds derived from vegetables and fruits, animal and microorganism derived compounds having antimicrobial properties can be potentially used in edible films as superior replcement for synthetic compounds, thus serving the purpose of quality and heath. Most of the natural antimicrobial agents enjoy GRAS status and are safer than their synthetic counterparts. This review focuses on updated literature on the sources, properties and potential applications of NAMAs in the food industry. This review also analyzes the biodegradability and biocompatibility and edibility properties of NAMAs enriched films and it can be concluded that NAMAs are better substitutes but affect the organoleptic as well as the mechanical properties of the films. Despite many advantages, the inclusion of NAMAs into the films needs to be investigated more to quantify the inhibitory concentration without affecting the properties of films and exerting potential antimicrobial action to ensure food safety.

Influence of chitosan-gelatin edible coating incorporated with longkong pericarp extract on refrigerated black tiger Shrimp (Penaeus monodon)

Chitosan-Gelatin (CHI-Gel) based edible coating incorporated with longkong pericarp extract (LPE) was developed and investigated for its impact on the quality of black tiger shrimp (Penaeus monodon) during refrigerated storage (4 ​°C) for 20 days. Shrimp coated with CHI-Gel-LPE (1.5%) had better quality indices than control (no coating), those coated with CHI, CHI-Gel, and CHI-Gel-LPE at lower concentrations (0.5 and 1%). The CHI-Gel-LPE inhibited melanosis and polyphenol oxidase (PPO) and controlled the pH changes in a dose-dependent manner. Lipid oxidation indices such as TBARS, PV, p-anisidine, and totox values were significantly controlled by the treatments throughout the storage. The CHI-GEL-LPE-1.5% coated sample had the lowest protein oxidation, and it's ascertained by the lowest loss of sulfhydryl groups, with the lowest carbonyl content throughout the storage (P ​< ​0.05). CHI-Gel-LPE (0.5-1.5%) coated samples had the lowest microbial growth (total viable count, lactic acid bacteria, Enterobacteriaceae, and Psychrotrophic bacteria) relative to the other treatments. Efficacy in quality maintenance of shrimp by LPE incorporated coating was improved with augmenting concentration used. Overall, LPE in the CHI-Gel edible coating served as a natural antioxidant, with antimicrobial activity and inhibiting melanosis, thus retain the quality and extend the shelf-life of shrimp stored at a refrigerated temperature.

Recent Advances in the Development of Smart and Active Biodegradable Packaging Materials

Interest in the development of smart and active biodegradable packaging materials is increasing as food manufacturers try to improve the sustainability and environmental impact of their products, while still maintaining their quality and safety. Active packaging materials contain components that enhance their functionality, such as antimicrobials, antioxidants, light blockers, or oxygen barriers. Smart packaging materials contain sensing components that provide an indication of changes in food attributes, such as alterations in their quality, maturity, or safety. For instance, a smart sensor may give a measurable color change in response to a deterioration in food quality. This article reviews recent advances in the development of active and smart biodegradable packaging materials in the food industry. Moreover, studies on the application of these packaging materials to monitor the freshness and safety of food products are reviewed, including dairy, meat, fish, fruit and vegetable products. Finally, the potential challenges associated with the application of these eco-friendly packaging materials in the food industry are discussed, as well as potential future directions.

Chitosan Films Functionalized with Different Hydroxycinnamic Acids: Preparation, Characterization and Application for Pork Preservation

Hydroxycinnamic acids are one category of bioactive phenolic acids that are widely distributed in plants. In this study, chitosan (CS) was functionalized with three kinds of hydroxycinnamic acids (p-coumaric acid, caffeic acid and ferulic acid) through the carbodiimide-mediated grafting method. The obtained hydroxycinnamic-acid-grafted CSs (hydroxycinnamic acid-g-CSs) were further fabricated into food packaging films through solvent casting. For the first time, the functionalities of the different hydroxycinnamic acid-g-CS films were compared. Results showed the grafting ratio of p-coumaric acid-g-CS, caffeic acid-g-CS and ferulic acid-g-CS was 73.68, 129.42 and 91.75 mg/g, respectively. Instrumental analyses confirmed hydroxycinnamic acids conjugated with CS through amide and ester bonds. The functionalization of CS film with hydroxycinnamic acids produced a more compact microstructure and higher UV light barrier ability, mechanical strength, water vapor barrier ability, thermal stability and antioxidant and antimicrobial activities. Among the different hydroxycinnamic acid-g-CS films, caffeic acid-g-CS film presented the strongest barrier, mechanical, antioxidant and antimicrobial properties. Moreover, caffeic acid-g-CS film packaging effectively extended the shelf life of pork to 10 days at 4 °C. Our results suggest caffeic acid-g-CS film can be used in the active food packaging field.

Essential Oil-Containing Polysaccharide-Based Edible Films and Coatings for Food Security Applications

The wastage of food products is a major challenge for the food industry. In this regard, the use of edible films and coatings have gained much attention due to their ability to prevent the spoilage of the food products during handling, transport, and storage. This has effectively helped in extending the shelf-life of the food products. Among the various polymers, polysaccharides have been explored to develop edible films and coatings in the last decade. Such polymeric systems have shown great promise in microbial food safety applications. The inclusion of essential oils (EOs) within the polysaccharide matrices has further improved the functional properties of the edible films and coatings. The current review will discuss the different types of polysaccharides, EOs, methods of preparing edible films and coatings, and the characterization methods for the EO-loaded polysaccharide films. The mechanism of the antimicrobial activity of the EOs has also been discussed in brief.

A critical review on intelligent and active packaging in the food industry: Research and development

The emergence of many new food products on the market with need of consumers to constantly monitor their quality until consuming, in addition to the necessity for reducing food corruption during preservation time, have led to the development of some modern packaging technologies such as intelligent packaging (IP) and active packaging (AP). The benefits of IP are detecting defects, quality monitoring and tracking the packaged food products to control the storage conditions from the production stage to the consumption stage by using various sensors and indicators such as time-temperature indicators (TTIs), gas indicators, humidity sensors, optical, calorimetric and electrochemical biosensors. While, AP helps to increase the shelf-life of products by using absorbing and diffusion systems for various materials like carbon dioxide, oxygen, and ethanol. However, there are some important issues over these emerging technologies including cost, marketability, consumer acceptance, safety and organoleptic quality of the food and emphatically environmental safety concerns. Therefore, future researches should be conducted to solve these problems and to prompt applications of IP and AP in the food industry. This paper reviews the latest innovations in these advanced packaging technologies and their applications in food industry. The IP systems namely indicators, barcoding techniques, radio frequency identification systems, sensors and biosensor are reviewed and then the latest innovations in AP methods including scavengers, diffusion systems and antimicrobial packaging are reviewed in detail.